A Case of Organizing Pneumonia Resembling Lung Cancer.

BACKGROUND: Organizing pneumonia (OP) is a pathologic diagnosis with clinical and imaging manifestations that often resemble other diseases, such as infections and cancers, which can lead to delays in diagnosis and inappropriate management of the underlying disease. In this article, we present a case of organized pneumonia that resembles lung cancer. METHODS: We report a case of initial suspicion of pulmonary malignancy, treated with anti-inflammatory medication and then reviewed with CT suggesting no improvement, and finally confirmed to be OP by pathological biopsy taken via transbronchoscopy. A joint literature analysis was performed to raise clinicians' awareness of the diagnosis and treatment of OP. RESULTS: Initially, because of the atypical auxiliary findings, we thought that the disease turned out to be a lung tumor, which was eventually confirmed as OP by pathological diagnosis. CONCLUSIONS: The diagnosis and treatment of OP requires a combination of clinical information and radiological expertise, as well as biopsy to obtain histopathological evidence. That is, clinical-imaging-pathological tripartite cooperation and comprehensive analysis.

[Clinical analysis of 4 children with cryptogenic organizing pneumonia].

Objective: To analyze the clinical features of children with cryptogenic organizing pneumonia (COP) confirmed by pathology. Methods: The clinical manifestations, imaging, pathology, treatment and outcome data of 4 children with COP confirmed by thoracoscopic lung biopsy were retrospectively analyzed, who were hospitalized at Respiratory Department of Shenzhen Children's Hospital from January 2004 to December 2022. Results: All of the 4 patients were male, the age ranged from 1 year 3 months to 14 years. The time from onset to diagnosis was 3 months to 3 years. The follow-up duration was 6 months to 6 years. All the 4 cases had cough, 2 cases had tachypnea and wheezing, 1 case had expectoration, 1 case had chest pain, 1 case had decreased activity tolerance and weight loss. Rales in 2 cases and hypoxemia in 1 case. Pulmonary high resolution CT showed diffuse distribution, involvement of both lungs in 3 cases, and single lung combined migration in 1 case.Three cases showed ground-glass opacity, consolidation, patchy or fibrous strips, and 1 case presented air bronchogram and "reversed halo sign". All the 4 cases were performed thoracoscopic lung biopsy, and the pathological findings showed cellulose exudate or small nodules filled with granulation tissue or fibroblasts in the alveolar cavity and small airways, and 1 case was Masson corpuscle positive. Three patients achieved remission after glucocorticoid therapy. Spontaneous remission without treatment was seen in 1 patient.Two cases were followed up for 17 months and 6 years, respectively, who had excellent outcome. Conclusions: The manifestations of COP in children include cough, expectoration and chest pain. Infants and young children may have tachypnea and wheezing. The most common chest CT findings are diffuse distribution of ground-glass opacity, patchy and consolidation in both lungs. Diagnosis should depend on pathological examination. The effect of glucocorticoid therapy is good.

Cryptogenic organizing pneumonia after withdrawal of systemic corticosteroids for chronic eosinophilic pneumonia and severe asthma under benralizumab treatment.

A 79-year-old woman with severe asthma developed chronic eosinophilic pneumonia (CEP). After CEP resolved with oral prednisolone at 30 mg/day, prednisolone was tapered and discontinued under introduction of benralizumab for her severe asthma. However, 8 weeks later, symptoms and bilateral patchy infiltrates on chest radiography appeared. Lymphocytosis without eosinophilia was seen in bronchoalveolar lavage fluids, and transbronchial biopsy indicated organizing pneumonia. Cryptogenic organizing pneumonia (COP) was diagnosed and resolved with prednisolone at 30 mg/day. Prednisolone was tapered to 3 mg/day without relapse of CEP or COP. This case suggests the overlap and similar pathogenesis of CEP and COP.

A case report: Acute fibrinous and organizing pneumonia.

RATIONALE: Acute fibrinous and organizing pneumonia (AFOP) is a rare acute or subacute interstitial lung disorder characterized by the deposition of fibrin within the alveoli and organizing pneumonia with a patchy distribution. The clinical features of AFOP are nonspecific, and it is often misdiagnosed as pneumonia, cancer, tuberculosis, or other lung disorders. PATIENT CONCERNS: In this case report, a 58-year-old woman presented with chest tightness, shortness of breath, cough and sputum. A chest CT scan showed multiple patchy shadows in both lungs. She was initially diagnosed with community-acquired pneumonia. Her purified protein derivative skin test was positive, but sputum was negative for acid-fast bacilli. DIAGNOSES: AFOP was diagnosed by bronchoscopic lung biopsy and histopathology. INTERVENTIONS: Following AFOP diagnosis, all anti-infective drugs were discontinued, and replaced by methylprednisolone and prednisone. OUTCOMES: After 1 week of treatment with methylprednisolone 40 mg daily, the patient chest CT and clinical symptoms improved. After 1 month, the patient symptoms had demonstrated dramatic improvement and CT scan revealed complete absorption of lesions in both lungs. After 5 months of follow-up, the patient symptoms completely disappeared. LESSONS: Acute AFOP is an uncommon lung condition with poor prognosis; hence, early diagnosis and identification are particularly important. Definitive diagnosis requires histopathological findings. Currently, there is no unified treatment guideline for AFOP, and treatment must be tailored based on the etiology and severity of each individual patient disease. Subacute AFOP shows a good response to corticosteroid treatment.

Properties of Pleural Mesothelial Cells in Idiopathic Pulmonary Fibrosis and Cryptogenic Organizing Pneumonia.

BACKGROUND: Profibrotic properties of pleural mesothelial cells may play an important role in the fibrosis activity in idiopathic pulmonary fibrosis (IPF). The purpose of this study was to compare the expression of pleural mesothelial cell markers in IPF and cryptogenic organizing pneumonia (COP), with an assumption that increased expression implies increase in fibrosis. METHODS: Twenty IPF lung samples were stained by immunohistochemistry for the pleural mesothelial cell markers: leucine rich repeat neuronal 4 (LRRN4), uroplakin 3B, CC-chemokine ligand 18, and laminin-5. Nine COP lung samples were used as controls. A semi-quantitative analysis was performed to compare markers expression in IPF and COP. RESULTS: LRRN4 expression was found in epithelial lining cells along the honeycombing and fibroblastic foci in IPF, but not in the fibrotic interstitial lesion and airspace filling fibrous tufts in COP. We found a significant decrease in baseline forced vital capacity when LRRN4 expression was increased in honeycombing epithelial cells and fibroblastic foci. CONCLUSION: LRRN4 expression patterns in IPF are distinct from those in COP. Our findings suggest that mesothelial cell profibrotic property may be an important player in IPF pathogenesis and may be a clue in the irreversibility of fibrosis in IPF.

Resolution of an insidious and migratory Mycobacterium tuberculosis-associated secondary organizing pneumonia: a case report and literature review.

BACKGROUND: Organizing pneumonia (OP) is a rare interstitial lung disease. Secondary organizing pneumonia (SOP) caused by Mycobacterium tuberculosis (MTB) is extremely rare. Migratory MTB-associated SOP is more deceptive and dangerous. When insidious tuberculosis (TB) is not recognized, SOP would be misdiagnosed as cryptogenic organizing pneumonia (COP). Use of steroid hormone alone leads to the progression of TB foci or even death. Clues of distinguishing atypical TB at the background of OP is urgently needed. CASE PRESENTATION: A 56-year-old female patient was hospitalized into the local hospital because of cough and expectoration for more than half a month. Her medical history and family history showed no relation to TB or other lung diseases. Community-acquired pneumonia was diagnosed and anti-infection therapy was initialized but invalid. The patient suffered from continuous weigh loss. More puzzling, the lesions were migratory based on the chest computed tomography (CT) images. The patient was then transferred to our hospital. The immunological indexes of infection in blood and pathogenic tests in sputum and the bronchoalveolar lavage fluid were negative. The percutaneous lung puncture biopsy and pathological observation confirmed OP, but without granulomatous lesions. Additionally, pathogen detection of the punctured lung tissues by metagenomics next generation sequencing test (mNGS) were all negative. COP was highly suspected. Fortunately, the targeted next-generation sequencing (tNGS) detected MTB in the punctured lung tissues and MTB-associated SOP was definitely diagnosed. The combined therapy of anti-TB and prednisone was administrated. After treatment for 10 days, the partial lesions were significantly resorbed and the patient was discharged. In the follow-up of half a year, the patient was healthy. CONCLUSIONS: It is difficult to distinguish SOP from COP in clinical practice. Diagnosis of COP must be very cautious. Transient small nodules and cavities in the early lung image are a clue to consider TB, even though all pathogen tests are negative. tNGS is also a powerful tool to detect pathogen, ensuring prompt diagnosis of TB-related SOP. For clinicians in TB high burden countries, we encourage them to keep TB in mind before making a final diagnosis of COP.

Organizing Pneumonia: A Clinical Challenge in a Child With Previous Rhabdomyosarcoma.

Organizing pneumonia is a pulmonary disease of undefined etiology, with few reported cases in children. It may be secondary to chemotherapy, radiation therapy, infectious agents, or hematopoietic cell transplantation. We present a case of an 18-year-old boy who presented to a follow-up consult with respiratory symptoms at the age of 11 years, 8 years after finishing treatment for a prostatic relapse of a pelvic rhabdomyosarcoma. Chest radiography revealed nodular opacities in the left lung, the one in the left lower lobe with silhouette sign with the left hemidiaphragm. Chest computerized tomography showed 2 nodular lesions in the left upper lobe, one of them cavitated, and another nodular lesion in the left lower lobe; 2 of these nodules had surrounding ground-glass opacities. Microbiological work-up, including tuberculosis screening, was negative. Biopsy revealed findings suggestive of organizing pneumonia. He presented spontaneous resolution. This case presented a diagnostic challenge due to rarity of this condition and its indetermined association with the patient's history of rhabdomyosarcoma. With this case, the authors alert that organizing pneumonia must be considered in patients presenting with pulmonary lesions with a history of previous hematopoietic stem cell transplants, lung irradiation, or immunosuppression. Pulmonary metastases and secondary tumors must be considered as a differential diagnosis in patients with a heavily treated relapsed rhabdomyosarcoma.

Secondary organizing pneumonia after recovery of mild COVID-19 infection.

A 36-year-old male with diffuse large B-cell lymphoma on maintenance rituximab therapy presented to the emergency department with high fever and fatigue. A chest X-ray showed a lobar infiltrate, 40 days before admission the patient suffered from a mild coronavirus disease 2019 (COVID-19) infection and fully recovered. PCR nasopharyngeal swab was negative for COVID-19. Comprehensive biochemical, radiological, and pathological evaluation including 18-fluorodeoxyglucose positron emission tomography with computed tomography and transbronchial lung biopsy found no pathogen or lymphoma recurrence. Treatment for pneumonia with antibiotic and antifungal agents was nonbeneficial. A diagnosis of secondary organizing pneumonia (OP) was made after pneumonia migration and a rapid response to corticosteroids. OP secondary to a viral respiratory infection has been well described. Raising awareness for post-COVID-19 OP has therapeutic and prognostic importance because those patients benefit from steroid therapy. We believe the condition described here is underdiagnosed and undertreated by doctors worldwide. Because of the ongoing global pandemic we are now encountering a new kind of patient, patients that have recovered from COVID-19. We hope that this case may contribute to gaining more knowledge about this growing patient population.

Acute fibrinous and organizing pfneumonia: two case reports and literature review.

BACKGROUND: Acute fibrinous and organizing pneumonia (AFOP) is a rare histologic interstitial pneumonia pattern characterized by the intra-alveolar fibrin deposition and organizing pneumonia. Its clinical characteristics are still not well known and there is no consensus on treatment yet. CASE PRESENTATION: We report two female cases in their fifties diagnosed with AFOP confirmed by a second lung biopsy. Case 1 was idiopathic AFOP with manifestation of 6-week fever, dyspnea, and cough, while case 2 was secondary to systemic lupus erythematosus and fever was the major symptom. Their chest CT scans revealed bilateral multiple consolidations, predominantly in the lower lobes. Both cases were initially diagnosed with pneumonia, but did not improve after treatment with broad-spectrum antibiotics. In both cases, transbronchial biopsy and bronchoalveolar lavage fluid examination were inconclusive and the pathological diagnosis was confirmed by percutaneous lung biopsy. Both patients had a good clinical response to prednisone. CONCLUSIONS: We report two rare AFOP cases to highlight the importance of awareness of this disease. We further perform the most comprehensive review to date in AFOP, including 150 patients since 2002. Consolidation was the most common imaging pattern, followed by ground-glass opacity and nodules. A lung biopsy is required for a definitive diagnosis. Corticosteroids is recommended as the most effective therapy, but treatment options should depend on the etiology and disease severity.

Organizing pneumonia in ALK+ lung adenocarcinoma treated with ceritinib: A case report and literature review.

RATIONALE: Anaplastic lymphoma kinase (ALK) inhibitors have been approved for patients with ALK-rearrangement lung cancer. The effect is superior to the standard first-line therapy of pemetrexed plus platinum-based chemotherapy. However, ALK inhibitors are associated with rare and sometimes fatal adverse events. Organizing pneumonitis (OP) is a rare and serious adverse event usually caused by ceritinib, and it is easily misdiagnosed as infectious pneumonia, metastasis, or cancer progression. PATIENT CONCERNS: A 56-year-old female presented with chest tightness and dyspnea for more than 10 days. She was previously healthy with no significant medical history. Workup including chest computed tomography (CT), pathological examination of a biopsy specimen, and next-generation sequencing was consistent with a diagnosis of IVA ALK-rearrangement lung adenocarcinoma. She was treated with pemetrexed plus platinum-based chemotherapy and crizotinib concurrently, followed by maintenance therapy with crizotinib alone and she had an almost complete response. However, about 26 months after beginning treatment she developed multiple brain metastases. Crizotinib was discontinued and she was begun on ceritinib. After about 3 months the brain metastases had almost complete response. After 5 months of ceritinib, however, multiple patchy lesions appeared in the bilateral upper lungs. DIAGNOSES: Treatment with antibiotics had no effect and blood and sputum cultures are negative. A CT-guided biopsy of the upper lung was performed, and pathological hematoxylin-eosin staining and immunohistochemical studies were consistent with OP. INTERVENTIONS: Ceritinib was discontinued, she was begun on prednisone 0.5 mg/kg orally every day, and regular follow-up is necessary. OUTCOMES: CT of the chest 2 and 4 weeks after beginning prednisone showed the lung lesions to be gradually resolving, and she was continued on prednisone for 2 months and gradually reduced the dose of prednisone every 2 weeks. No related adverse events were occurred in patient. LESSONS: OP must be differentiated from infectious pneumonia, metastasis, or cancer progression. The mechanism of OP is still unknown and needs further research. Biopsy plays a role in making a diagnosis of OP. In our patient, discontinuing ceritinib and treating her with prednisone resulted in a good outcome.

Clinical features of acute fibrinous and organizing pneumonia: An early histologic pattern of various acute inflammatory lung diseases.

BACKGROUND: Acute fibrinous and organizing pneumonia (AFOP) is a rare histologic pattern of acute lung involvement with intra-alveolar fibrin deposition. However, the clinical significance of the pathological findings of AFOP remains unclear. This study aimed to explore the clinical significance of AFOP through a comprehensive clinical examination. METHODS: The medical records of patients with lung diseases accompanied by the pathological finding of intra-alveolar organization between January 2010 and December 2019 were retrospectively reviewed. The clinical and radiological findings were compared between the groups with and without the histologic pattern of AFOP. RESULTS: We identified 34 patients with AFOP (AFOP group) and 143 without AFOP (non-AFOP group). The underlying diseases of the AFOP group were as follows: 19 patients had cryptogenic organizing pneumonia (OP), 5 had connective tissue diseases, 3 had radiation pneumonitis, 3 had chronic eosinophilic pneumonia, 2 had myelodysplastic syndromes, and 2 had drug-induced pneumonia. Fever was more common, the time from symptom onset to biopsy was shorter, and the serum C-reactive protein level was higher in the AFOP group than in the non-AFOP group. On high-resolution computed tomography, 85% of patients had OP pattern, and halo sign was more common in the AFOP group. Corticosteroids were effective in 94% of the patients in the AFOP group; however, recurrences were more frequent, and a higher corticosteroid dose was needed during recurrence. CONCLUSIONS: AFOP might be an early phase of a histologic pattern associated with known etiologies. In addition, it could be a marker indicating intense inflammatory diseases with a tendency of recurrence.

Diagnostic yield, safety, and impact of transbronchial lung biopsy in mechanically ventilated, critically ill patients: a retrospective study.

BACKGROUND: Pulmonary infiltrates of variable etiology are one of the main reasons for hypoxemic respiratory failure leading to invasive mechanical ventilation. If pulmonary infiltrates remain unexplained or progress despite treatment, the histopathological result of a lung biopsy could have significant impact on change in therapy. Surgical lung biopsy is the commonly used technique, but due to its considerable morbidity and mortality, less invasive bronchoscopic transbronchial lung biopsy (TBLB) may be a valuable alternative. METHODS: Retrospective, monocentric, observational study in mechanically ventilated, critically ill patients, subjected to TBLB due to unexplained pulmonary infiltrates in the period January 2014 to July 2019. Patients' medical records were reviewed to obtain data on baseline clinical characteristics, modality and adverse events (AE) of the TBLB, and impact of the histopathological results on treatment decisions. A multivariable binary logistic regression analysis was performed to identify predictors of AE and hospital mortality, and survival curves were generated using the Kaplan-Meier method. RESULTS: Forty-two patients with in total 42 TBLB procedures after a median of 12 days of mechanical ventilation were analyzed, of which 16.7% were immunosuppressed, but there was no patient with prior lung transplantation. Diagnostic yield of TBLB was 88.1%, with AE occurring in 11.9% (most common pneumothorax and minor bleeding). 92.9% of the procedures were performed as a forceps biopsy, with organizing pneumonia (OP) as the most common histological diagnosis (54.8%). Variables independently associated with hospital mortality were age (odds ratio 1.070, 95%CI 1.006-1.138; p = 0.031) and the presence of OP (0.182, [0.036-0.926]; p = 0.040), the latter being confirmed in the survival analysis (log-rank p = 0.040). In contrast, a change in therapy based on histopathology alone occurred in 40.5%, and there was no evidence of improved survival in those patients. CONCLUSIONS: Transbronchial lung biopsy remains a valuable alternative to surgical lung biopsy in mechanically ventilated critically ill patients. However, the high diagnostic yield must be weighed against potential adverse events and limited consequence of the histopathological result regarding treatment decisions in such patients.

Idiopathic focal organizing pneumonia mimicking malignancy.

Idiopathic FOP is a rare type of COP. What we know on this subject is made up of a few clinical cases published in recent years. Our patient was admitted to the hospital with an intermittent coughing complaint that worsens over time. Due to a suspicion of malignancy, a radiological evaluation was requested including a PET-CT and a transbronchial biopsy was performed. Until the last part of our algorithm, the patient profile was clinically and radiologically in favor of the diagnosis of malignancy but, in the end, the diagnosis of FOP was fixed with a follow-up decision. In conclusion, FOP is a relatively new entity that should be kept in mind in the differential diagnosis of malignancy.

Pulmonary tuberculosis presenting secondary organizing pneumonia with organized polypoid granulation tissue: case series and review of the literature.

BACKGROUND: Secondary organizing pneumonia (SOP) is difficult to distinguish from cryptogenic organizing pneumonia (COP) considering various clinical situations. SOP caused by Mycobacterium tuberculosis is rare; indeed, it has not been reported as a sequela of disseminated tuberculosis. METHODS: From January 2016 to December 2018, we identified six cases of tuberculosis-associated SOP in which Mycobacterium tuberculosis was revealed by microbiological examination; one of the cases was miliary tuberculosis. RESULTS: Of the six cases, 17% were positive for acid fast bacillus (AFB) stain, but 100% were positive for M. tuberculosis polymerase chain reaction (MTB PCR) and AFB culture. In all cases, transbronchial lung biopsy was performed and organizing pneumonia was confirmed pathologically. All survived after treatment with anti-tuberculosis therapy. CONCLUSIONS: Pulmonary tuberculosis, which shows OP in lung biopsy, is diagnosed through MTB PCR and AFB culture, and the prognosis is thought to be good.

Neumonia crónica organizada en un adolescente: presentación de un caso / Chronic organized pneumonia in an adolescent: presentation of a case

We present a case of organized chronic pneumonia (OCP), a rare interstitial disease, which usually affects people over 50 years of age and is very unusual in pediatrics, so we thought it was of interest to communicate it. Is a 14-year-old male in whom in the study of a febrile condition, a pneumonia of LII was detected. The images persist after 2 months of being treated and being asymptomatic. Infectious causes and rheumatic diseases were ruled out due to the history of discoid lupus. Chest CT, bronchoalveolar lavage and lung biopsy showing Masson's bodies were performed and OCP was diagnosed. He received prednisone 1 mg / kg day and Clarithromycin for 2 months with rapid improvement. Relapses with new radiological images typical of OCP twice, when treating on alternate days. It is indicated prednisone 30 mgr / day for 3 months and gradual reduction. At 18 months, being with prednisone 5 mgr day, has a relapse of rapid progression that was treated with pulses of methylprednisolone. The collagen study shows positive lupus anticoagulant and ANA and Systemic Lupus is diagnosed. The bad evolution would be explained because it was a secondary OCP. Mycophenolate associated with prednisone was indicates, which has been used in the OCP and in Lupus. This clinical case shows the importance of radiological follow-up of patients with OCP and the search for secondary OCP causes due to the poor response to corticosteroids.

Se presenta un caso de neumonía crónica organizada (NCO), enfermedad intersticial rara, que afecta habitualmente a mayores de 50 años y muy inusual en pediatría, por lo que creímos de interés comunicarlo. Se trata de un varón de 14 años en el que en el estudio de un cuadro febril se detecta una neumonía de LII cuyas imágenes persisten luego de 2 meses de haber sido tratado y estando asintomático. Se descartaron causas infecciosas y enfermedades reumatológicas por el antecedente de lupus discoide. Se realizó TC de tórax, lavado broncoalveolar y biopsia pulmonar que mostró cuerpos de Masson, con lo que se diagnosticó NCO. Recibió prednisona 1 mgr/ kg día y Claritromicina por 2 meses con una rápida mejoría. Recae con nuevas imágenes radiológicas típicas de NCO dos veces, al pasar de tratamiento diario a días alternos. Se indica 30 mgr/día por 3 meses de prednisona y reducción gradual posterior. A los 18 meses de tratamiento, estando con prednisona 5 mgr día, tiene una recaída de rápida progresión que se trató con pulsos de metilprednisolona. El estudio de colagenosis muestra anticoagulante lúpico y ANA positivos y se diagnóstica Lupus Sistémico. La mala evolución se explicaría porque se trató de una NCO secundaria, ante lo cual indicó micofenolato asociado a prednisona, que se ha usado en la NCO y en el Lupus. Este caso clínico muestra la importancia del seguimiento radiológico de los pacientes con NCO y de la búsqueda de causas secundarias de NCO ante la mala respuesta a corticoides